In one method, known as "over-the-partition hand burning" (riser construction), vertical lead risers from cell elements which sandwich an intervening rubber or plastic partition are melted over the partition and fused manually, using a gas torch. A metal or ceramic mold is used to contain the molten lead. The fused, cooled lead forms the intercell connection.
In another method, known as "through-the-partition hand burning" (pin & ring construction), a lead pin extends horizontally from the lead tombstone of the positive strap of one cell element, through a round orifice in the intervening rubber or plastic partition, and into a horizontal round orifice (ring) in the lead tombstone of the negative strap of the element in the adjacent cell. The positive pin and negative ring are melted and fused manually, using a gas torch. A metal or ceramic mold is used to contain the molten lead. The fused, cooled lead forms the intercell connection.
In another method, known as "intercell reistance welding" (flat tombstone construction), vertical flat lead tombstones from the straps of elements in adjacent cells are positioned over a round orifice in the intervening rubber or plastic partition. Electrodes deform the tombstones until they make contact within the orifice in the partition. Current is then applied across the two tombstones; internal and contact resistance creates heat to melt and fuse the tombstones within the orifice in the partition. The fused, cooled lead forms the intercell connection.
In another method, known as "over-the-partition induction heated intercell fusion" (riser construction), vertical lead risers from cell elements adjacent to an intervening rubber or plastic partition are melted and fused using induction heat. A mold is used to contain the molten lead. The fused, cooled lead forms the intercell connection.
In another method, known as "through-the-partition induction heated intercell fusion" (pin & ring construction), a lead pin extends horizontally from the lead tombstone of the positive strap of one cell element, through a round orifice in the intervening rubber or plastic partition, and into a horizontal round orifice (ring) in the lead tombstone of the negative strap of the element in the adjacent cell. The positive pin and negative ring are melted and fused using induction heat. No mold is used to contain the molten lead. The fused, cooled lead forms the intercell connection.
Over-the-partition hand burning, and through-the-partition hand burning (both described above) are manual operations; thus, they are relatively slow and yield intercell connections of inconsistent and unreliable quality.
Intercell resistance welding (described above) has been automated and is relatively fast, but it produces intercell connections of inconsistent and unreliable quality.
Through-the-partition induction heated intercell with pin & ring construction (described above) requires male and female parts which are relatively difficult to cast as compared to flat tombstones.
The subject process, Intercell Fusion Through Battery Flat Tombstones, differs markedly from previously patented processes as described below.
U.S. Pat. No. 3,544,754, granted Dec. 1, 1970, to Buttke, et al., and related patents refer to a method and apparatus for fusing lead/acid battery intercell terminals using "extrusion fusion" and resistance welding. Vital to this process, is the principle of extruding lead through an orifice in the battery container partition. Since, in the present invention, insufficient external pressure is supplied to extrude the lead, and since induction heating (not resistance welding) is utilized, U.S. Pat. No. 3,544,754 does not apply.
U.S. Pat. No. 3,589,948, granted June 29, 1971, to Adams, refers to various techniques, including induction heating, used to fuse intercell connections (with flat tombstones) through an orifice in battery container partitions. This patent specifies the use of a "mold" to "contain" the molten lead. The present invention uses no molds to contain the molten lead; therefore, U.S. Pat. No. 3,589,948 does not apply.
U.S. Pat. No. 4,501,943, granted Feb. 26, 1985, to Lund, and U.S. Pat. No. 4,523,068, granted June 11, 1985 to Lund, et al., refer to a method and apparatus for fusing external battery top terminal posts. These patents specify the use of a "concentric mold" to contain the molten lead. Since the process detailed here refers to fusion of intercell connectors inside the battery, not external top terminal posts, and because molds are not used to contain the molten lead, U.S. Pat. Nos. 4,501,943 and 4,523,068 do not apply.
U.S. Pat. No. 3,336,164, granted Aug. 15, 1967 to Miller, and related patents, refer to method and apparatus for fusing internal intercell connections with pin & ring construction using manual gas torch "burning". Since the process detailed in applicants invention employs flat tombstones (not male and female "pin & ring" tombstones), U.S. Pat. No. 3,336,164 does not apply.